Stop-watch.



PATENTED JUNE 27, 1905.

W. E. PORTER.

STOP WATCH.

APPLICATION FILED JAN.'16, 1902.

INVENTOR B) @1124 'A77'0RNEYS.

wmvsssss ,azww

UNITED STATES IVILSON E. PORTER, OF NE\V HAVEN, CONNECTICUT, ASSIGNOR TO THE NEIV HAVEN CLOCK CO., OF NEIV HAVEN, CONNECTICUT, A CORPORA- TION OF CONNECTICUT.

latented June 27, 1905.

PATENT OFFICE.

STOP-WATCH.

SPECIFICATION forming part of Letters Patent No. 793,320, dated June 27, 1905.

Application filed January 16, 1902. Serial No. 90,011.

To a. whom it 71711.7 concern/.-

Be it known that I, \VILsoN E. Porrrnnpf the city and county of New Haven and State of Connecticut, have invented a new and useful 5 Improvement in Stop-\Vatches, of which the following is a full, clear, and exact description when taken in connection with the accompanying drawings, which form a part thereof, and in which- Figure 1 represents a top view of the portions of the watch comprising my invention, the sweep seconds-hand being shown in its released position; Fig. 2,'a similar view, the seconds-hand being in its checked position; 5 Fig. 3, a similar view of the portion comprising the fly-back mechanism, the seconds-hand having been returned to its original position;

Fig. 4, a bottom view of the movement-plate of the watch, showing the parts of my inven- 20 tion located on the under side of the movement-plate; Fig. 5, a vertical section on lines 5 5 of Fig. A; Fig. 6, an end view of the movement-plate and parts comprising my invention, the stem of the watch being omitted; and Fig. 7,an enlarged vertical section through the central portion of the watch.

In all figures similar letters of reference represent like parts.

This invention relates to stop-watches; and it consists of various improvements and combinations of parts, as described and claimed hereinafter.

One object of the invention is to provide mechanism by which a so-called sweep seconds-hand may be applied without any material change of construction to an ordinary watch in such manner that the hand may be driven by the regular time-train for any desired period, then checked independently of 4 said train and returned to its original position, the various movements being effected by successive pressure on the stem of the watch.

For a more particular description reference is made to the drawings, in which the parts designated by the letter A represent the movementplate of the watch, upon which are mounted the various parts of the invention.

B designates the usual stem of the watch, which may be provided with a spring (not shown) for holding it in its extended position in well-known manner.

The usual time-train and setting-train are not shown nor described, the description being limited to the parts which contribute to the invention, as the connection between the time-train and sweep seconds-hand may be readily understood by any one familiar with the art. A gear C, however, is indicated in Figs. 1, 2, and 5 to represent the drivingwheel of the shaft 0, Figs. 5 and 7, upon which the sleeve (Z of the sweep seconds-hand D is f rictionally mounted. The gear C may obviously be connected in any suitable manner with the time-train of the watch, so as to drive the shaft 0 at the proper rate of speed. The sleeve (Z and sweep seconds hand D through its frictional connection are therefore adapted to rotate with the shaft at the seconds-hand rate.

To stop the movement of the seconds-hand D at any desired point and to return it to its original position, the following mechanism is provided: A push-bar E is mounted on the under side of the plate A and is held thereto by means of two screws F and G, the screw F passing from the top of the movement-plate through a slot f therein and being screwed into the bar E and the screw Cr passing through a slot g in the bar E and being screwed into the under side of the plate A. The slotf, as shown more particularly in Fig. 2, is of substantially semicircular form. The bar E at one end is provided with a short portion extending at right angles to the main part thereof and which is provided with a groove H, open at one end. The stem B has at its inner end a reduced portion 7/, with a head Z), which reduced portion may take into the slot H, thereby engaging the stem B and bar E. The bar E has on one side a lug I adapted to engage the teeth of a ratchet-wheel J, having a pawl K and spring 71?.

Pressure upon the end of the stem B forces the push-bar E in substantially a longitudinal direction, so that the lug I will engage a tooth of the ratchet-wheel J and turn the wheel J slightly on its pivot. The spring (not shown) of the stem B will return the stem to its extended position upon its being released from the pressure of the operator, and the stem B will in turn draw the bar E backward, the lug I being permitted to pass over the teeth of the wheel J (which is held from reverse movement by the pawl K) by means of the slight transverse play of the screw F in the slot f and of the end of the stem B in the groove H.

On the same pivot with the ratchet-wheel J, but on the upper side of the plate A, a fourleaf cam-wheel L is rigidly mounted, so that it will rotate with the wheel J. On one side of the cam L is pivoted the stop-lever M, with a lug m adapted to bear on the periphery of the cam under the pressure of a spring N. On the opposite side of the cam L is pivoted the fly-back lever P, provided with a lug 1), adapted to bear also on the periphery of the cam L under the pressure of a spring 0. The cam L is adapted to assume three successive positions with regard to the two levers M and P, as shown in Figs. 1, 2, and 3. In the first position both levers ride upon the wider portions of the cam, so that both are swung outward against the pressure of the springs N and O, respectively, Fig. 1. In the second position the lug m of the stoplever M drops into one of the notches l between the leaves of the cam, so that the lever M is swung inward by the spring N, while the fly-back lever P is still held in its outer position, Fig. 2. In assuming the third position the stop-lever is forced gradually outward, and the lug p of the fly-back lever P drops into one of the notches Z, which permits the lever P to be swung inward by its spring 0, Fig. 3. These successive positions of the cam L correspond to the .movement of the wheel J upon the engageed to bear against the periphery of the disk R when the stop-lever M is in the position shown in Fig. 2 of the drawings, and in such position the pressure of the lever M upon the disk R is sufficiently great to overcome the frictional connection between the sleeve d and the shaft 0, so that the sleeve d and the seconds-hand D are prevented from further movement with the time-train of the watch. The fly-back lever P is provided at its free end with a depending pin V, adapted to move in a slot W in the movement-plate A, and when the lever P is at its inner position (shown in Fig. 3) the pin V will bear upon the periphery of the heart-shaped cam S and in well-known manner rotate the cam, and consequently the seconds-hand D, to its original position, as shown in Fig. 3. As pointed out above, the same movement of the camwheel L which permits the fly-back lever P to assume this position forces the stop-lever M outward away from the disk R.

The heart-shaped cam S and the secondshand D are held in their normal positions by the fly-back lever P until the same is released by the movement of the cam-wheel L, which forces the fly-back lever P away from the cam S, as shown in Fig. 1. In this position the stop-lever M is also held away from the disk R, so that the seconds-hand D is free to rotate with the shaft 0 of the time-train wheel O through its frictional connection until the further movement of the cam-wheel L brings the lever T again into contact with the disk R.

Having now described my invention, (which may vary in its details without departing from the spirit thereof,) what I claim, and desire to secure by Letters Patent, is

In a watch, the combination with the stem;

hand on the Mth day of January, 1902.

WILSON E. PORTER.

Witnesses:

GEoReIE T. NoLIN, M. E. SMITH. 

